Audio to MIDI Converter Team Obama Advisor: Dr. William Hunt Adnan Burkic Sean Earley Jon Kump Brian Tyson Georgia Institute of Technology 4/27/2010

Project Overview Audio to MIDI converter plug-in designed for guitar Guitar can control any MIDI device in real-time Software will be targeted toward guitarists and record producers Software solution requiring no hardware Software will be approximately $50, cheaper than competing hardware products

Design Overview

Design Goals VST plug-in compatible with any third-party software Low latency to allow real-time performance Fast and accurate pitch detection (monophonic) Pitch bend capability Intuitive, easy to use interface

VST Compatibility Compatible with most digital audio workstations (DAWs), but not all DAW needs to support receiving MIDI events from VST plugin If DAW is not supported, program can be run as stand-alone executable

Latency Difference in time DAW receives guitar note to time synthesizer plays sound Optimally less than 20ms Measured difference using host program

Latency Measurement Top waveform is guitar audio Bottom waveform is synthesizer audio Each square of bottom grid represents 20ms By using a pixel ruler, average latency was found to be 23.8ms

Pitch Detection Each note played on guitar needs to generate correct MIDI note Easy to verify by simply playing each note on guitar and verify correct MIDI note is output Pitch detection was found to be accurate for every possible note on a standard tuned guitar

Pitch Bend Feature was successfully implemented Performance varies depending on note played and degree of bend Can be enabled or disabled as needed

Graphical User Interface

Demonstration Illustration

Marketable Changes Improved latency Optimized pitch bend Expand to more third-party software Support for non standard tunings Support for other instruments

Questions?